File extensions

Nick Phillips nwp at LEMON-COMPUTING.COM
Mon Sep 3 11:42:45 IST 2001

On Mon, Sep 03, 2001 at 10:55:23AM +0100, Jethro R Binks wrote:
> Hi folks,
> I've been asked to add ".sit" for Macintosh Stuffit Expander ("Stuffit
> Archive - Binary" according to one source) files on to the allow list for
> MailScanner's filename checking.  I note that there is already ".sit.bin"
> in the default list -- are they representing the same thing?  Would one
> expect one extension over the other?

.sit is a basic stuffit archive, .sit.bin is a BinHex-ed version of that
(equivalent to uuencoding). Probably. It gets really confusing on macs
which archiver does what, as they all seem to have gradually picked up
abilities from each other.

> On a similar note, I added .sea for Self Extracting Archive, another Mac
> one.  Is there any notable danger in that?  I guess it is no worse than
> allowing plain Windows .exe through.

Fairly bad, then, given that users probably won't realise that it's an
executable they're clicking on.

The other two invoke whatever program the user has installed on their
machine that associates with that type, but a self-extractor could be
anything (I guess, I don't know whether an .sea has a different type
associated with it than a straight executable - macs don't rely on the
extension to find the program to use).

.sit and .sit.bin and .hqx are the equivalent of .zip as far as danger

.sea is probably a different kettle of fish. Potentially the equivalent
of .vbs.jpg ;)


Nick Phillips -- nwp at
Beware of a dark-haired man with a loud tie.

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